diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 1457062053..59c650e8b7 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -207,7 +207,12 @@ jobs:
       - name: Upload combined results
         uses: actions/upload-artifact@v4
         with:
-          name: Unit Test Results ${{ matrix.target.os }}-${{ matrix.target.cpu }}
+          # upload-artifact requires avoiding "/", because "To maintain file
+          # system agnostic behavior, these characters are intentionally not
+          # allowed to prevent potential problems with downloads on different
+          # file systems". However, GitHub Actions workflows do not support a
+          # usual assortment of string functions.
+          name: Unit Test Results ${{ matrix.target.os }}-${{ matrix.target.cpu }}-${{ matrix.branch == 'upstream/version-2-0' && 'version-2-0' || matrix.branch }}
           path: build/*.xml
 
   devbuild:
diff --git a/beacon_chain/consensus_object_pools/blockchain_dag.nim b/beacon_chain/consensus_object_pools/blockchain_dag.nim
index 0a5fe0627b..369560b921 100644
--- a/beacon_chain/consensus_object_pools/blockchain_dag.nim
+++ b/beacon_chain/consensus_object_pools/blockchain_dag.nim
@@ -1,5 +1,5 @@
 # beacon_chain
-# Copyright (c) 2018-2024 Status Research & Development GmbH
+# Copyright (c) 2018-2025 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
@@ -1639,11 +1639,11 @@ template forkAtEpoch*(dag: ChainDAGRef, epoch: Epoch): Fork =
   forkAtEpoch(dag.cfg, epoch)
 
 proc getBlockRange*(
-    dag: ChainDAGRef, startSlot: Slot, skipStep: uint64,
+    dag: ChainDAGRef, startSlot: Slot,
     output: var openArray[BlockId]): Natural =
   ## This function populates an `output` buffer of blocks
   ## with a slots ranging from `startSlot` up to, but not including,
-  ## `startSlot + skipStep * output.len`, skipping any slots that don't have
+  ## `startSlot + output.len`, skipping any slots that don't have
   ## a block.
   ##
   ## Blocks will be written to `output` from the end without gaps, even if
@@ -1657,7 +1657,7 @@ proc getBlockRange*(
     headSlot = dag.head.slot
 
   trace "getBlockRange entered",
-    head = shortLog(dag.head.root), requestedCount, startSlot, skipStep, headSlot
+    head = shortLog(dag.head.root), requestedCount, startSlot, headSlot
 
   if startSlot < dag.backfill.slot:
     debug "Got request for pre-backfill slot",
@@ -1671,11 +1671,9 @@ proc getBlockRange*(
     runway = uint64(headSlot - startSlot)
 
     # This is the number of blocks that will follow the start block
-    extraSlots = min(runway div skipStep, requestedCount - 1)
+    extraSlots = min(runway, requestedCount - 1)
 
-    # If `skipStep` is very large, `extraSlots` should be 0 from
-    # the previous line, so `endSlot` will be equal to `startSlot`:
-    endSlot = startSlot + extraSlots * skipStep
+    endSlot = startSlot + extraSlots
 
   var
     curSlot = endSlot
@@ -1687,7 +1685,7 @@ proc getBlockRange*(
     if bs.isSome and bs.get().isProposed():
       o -= 1
       output[o] = bs.get().bid
-    curSlot -= skipStep
+    curSlot -= 1
 
   # Handle start slot separately (to avoid underflow when computing curSlot)
   let bs = dag.getBlockIdAtSlot(startSlot)
diff --git a/beacon_chain/nimbus_beacon_node.nim b/beacon_chain/nimbus_beacon_node.nim
index 7e772037cd..7aaf93ca48 100644
--- a/beacon_chain/nimbus_beacon_node.nim
+++ b/beacon_chain/nimbus_beacon_node.nim
@@ -1595,7 +1595,7 @@ proc pruneBlobs(node: BeaconNode, slot: Slot) =
     var blocks: array[SLOTS_PER_EPOCH.int, BlockId]
     var count = 0
     let startIndex = node.dag.getBlockRange(
-      blobPruneEpoch.start_slot, 1, blocks.toOpenArray(0, SLOTS_PER_EPOCH - 1))
+      blobPruneEpoch.start_slot, blocks.toOpenArray(0, SLOTS_PER_EPOCH - 1))
     for i in startIndex..<SLOTS_PER_EPOCH:
       let blck = node.dag.getForkedBlock(blocks[int(i)]).valueOr: continue
       withBlck(blck):
diff --git a/beacon_chain/sync/sync_protocol.nim b/beacon_chain/sync/sync_protocol.nim
index af61fc5d8a..1bd7e1dc39 100644
--- a/beacon_chain/sync/sync_protocol.nim
+++ b/beacon_chain/sync/sync_protocol.nim
@@ -9,7 +9,6 @@
 
 import
   chronicles, chronos, snappy, snappy/codec,
-  ../spec/datatypes/[phase0, altair, bellatrix, capella, deneb],
   ../spec/[helpers, forks, network],
   ".."/[beacon_clock],
   ../networking/eth2_network,
@@ -167,7 +166,7 @@ template getBlobSidecarsByRange(
     count = int min(reqCount, blockIds.lenu64)
     endIndex = count - 1
     startIndex =
-      dag.getBlockRange(startSlot, 1, blockIds.toOpenArray(0, endIndex))
+      dag.getBlockRange(startSlot, blockIds.toOpenArray(0, endIndex))
 
   var
     found = 0
@@ -222,12 +221,11 @@ p2pProtocol BeaconSync(version = 1,
     #      client call that returns `seq[ref ForkedSignedBeaconBlock]` will
     #      will be generated by the libp2p macro - we guarantee that seq items
     #      are `not-nil` in the implementation
-    # TODO reqStep is deprecated - future versions can remove support for
-    #      values != 1: https://github.com/ethereum/consensus-specs/pull/2856
-
-    trace "got range request", peer, startSlot,
-                               count = reqCount, step = reqStep
-    if reqCount == 0 or reqStep == 0:
+    trace "got range request", peer, startSlot, count = reqCount
+    # https://github.com/ethereum/consensus-specs/pull/2856
+    if reqStep != 1:
+      raise newException(InvalidInputsError, "Step size must be 1")
+    if reqCount == 0:
       raise newException(InvalidInputsError, "Empty range requested")
 
     var blocks: array[MAX_REQUEST_BLOCKS.int, BlockId]
@@ -236,9 +234,8 @@ p2pProtocol BeaconSync(version = 1,
       # Limit number of blocks in response
       count = int min(reqCount, blocks.lenu64)
       endIndex = count - 1
-      startIndex =
-        dag.getBlockRange(startSlot, reqStep,
-                          blocks.toOpenArray(0, endIndex))
+      startIndex = dag.getBlockRange(
+        startSlot, blocks.toOpenArray(0, endIndex))
 
     var
       found = 0
@@ -268,8 +265,7 @@ p2pProtocol BeaconSync(version = 1,
 
         inc found
 
-    debug "Block range request done",
-      peer, startSlot, count, reqStep
+    debug "Block range request done", peer, startSlot, count
 
   proc beaconBlocksByRoot_v2(
       peer: Peer,
@@ -459,7 +455,7 @@ p2pProtocol BeaconSync(version = 1,
       count = int min(reqCount, blockIds.lenu64)
       endIndex = count - 1
       startIndex =
-        dag.getBlockRange(startSlot, 1, blockIds.toOpenArray(0, endIndex))
+        dag.getBlockRange(startSlot, blockIds.toOpenArray(0, endIndex))
 
     var
       found = 0
diff --git a/ncli/ncli_db.nim b/ncli/ncli_db.nim
index 2f67345b04..9c0bff1897 100644
--- a/ncli/ncli_db.nim
+++ b/ncli/ncli_db.nim
@@ -1,5 +1,5 @@
 # beacon_chain
-# Copyright (c) 2020-2024 Status Research & Development GmbH
+# Copyright (c) 2020-2025 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
@@ -8,7 +8,7 @@
 {.push raises: [].}
 
 import
-  std/[os, stats, tables],
+  std/tables,
   snappy,
   chronicles, confutils, stew/[byteutils, io2], eth/db/kvstore_sqlite3,
   ../beacon_chain/networking/network_metadata,
@@ -21,6 +21,9 @@ import
   ../research/simutils,
   ./era, ./ncli_common, ./validator_db_aggregator
 
+from std/os import createDir, dirExists, moveFile, `/`
+from std/stats import RunningStat
+
 when defined(posix):
   import system/ansi_c
 
@@ -641,7 +644,7 @@ proc cmdExportEra(conf: DbConf, cfg: RuntimeConfig) =
       if firstSlot.isSome():
         withTimer(timers[tBlocks]):
           var blocks: array[SLOTS_PER_HISTORICAL_ROOT.int, BlockId]
-          for i in dag.getBlockRange(firstSlot.get(), 1, blocks)..<blocks.len:
+          for i in dag.getBlockRange(firstSlot.get(), blocks)..<blocks.len:
             if not dag.getBlockSZ(blocks[i], tmp):
               break writeFileBlock
             group.update(e2, blocks[i].slot, tmp).get()
@@ -901,11 +904,11 @@ proc createInsertValidatorProc(db: SqStoreRef): auto =
     VALUES(?, ?);""",
     (int64, array[48, byte]), void).expect("DB")
 
-proc collectBalances(balances: var seq[uint64], forkedState: ForkedHashedBeaconState) =
+func collectBalances(balances: var seq[uint64], forkedState: ForkedHashedBeaconState) =
   withState(forkedState):
     balances = seq[uint64](forkyState.data.balances.data)
 
-proc calculateDelta(info: RewardsAndPenalties): int64 =
+func calculateDelta(info: RewardsAndPenalties): int64 =
   info.source_outcome +
   info.target_outcome +
   info.head_outcome +
diff --git a/scripts/launch_local_testnet.sh b/scripts/launch_local_testnet.sh
index 99d2e0e7ee..fe8e006676 100755
--- a/scripts/launch_local_testnet.sh
+++ b/scripts/launch_local_testnet.sh
@@ -1,16 +1,13 @@
 #!/usr/bin/env bash
 
-# Copyright (c) 2020-2024 Status Research & Development GmbH. Licensed under
+# Copyright (c) 2020-2025 Status Research & Development GmbH. Licensed under
 # either of:
 # - Apache License, version 2.0
 # - MIT license
 # at your option. This file may not be copied, modified, or distributed except
 # according to those terms.
 
-# Mostly a duplication of "tests/simulation/{start.sh,run_node.sh}", but with a focus on
-# replicating testnets as closely as possible, which means following the Docker execution labyrinth.
-
-set -euo pipefail
+set -Eeuo pipefail
 
 SCRIPTS_DIR="$(dirname "${BASH_SOURCE[0]}")"
 cd "$SCRIPTS_DIR/.."
@@ -881,7 +878,7 @@ fi
 
 jq -r '.hash' "$EXECUTION_GENESIS_BLOCK_JSON" > "${DATA_DIR}/deposit_contract_block_hash.txt"
 
-for NUM_NODE in $(seq 1 $NUM_NODES); do
+for NUM_NODE in $(seq 1 "${NUM_NODES}"); do
   NODE_DATA_DIR="${DATA_DIR}/node${NUM_NODE}"
   rm -rf "${NODE_DATA_DIR}"
   scripts/makedir.sh "${NODE_DATA_DIR}" 2>&1
@@ -922,7 +919,7 @@ DIRECTPEER_ENR=$(
 
 cp "$SCRIPTS_DIR/$CONST_PRESET-non-overriden-config.yaml" "$RUNTIME_CONFIG_FILE"
 # TODO the runtime config file should be used during deposit generation as well!
-echo Wrote $RUNTIME_CONFIG_FILE:
+echo Wrote "${RUNTIME_CONFIG_FILE}":
 tee -a "$RUNTIME_CONFIG_FILE" <<EOF
 PRESET_BASE: ${CONST_PRESET}
 MIN_GENESIS_ACTIVE_VALIDATOR_COUNT: ${TOTAL_VALIDATORS}
@@ -1157,7 +1154,7 @@ for NUM_NODE in $(seq 1 "${NUM_NODES}"); do
         fi
       done
 
-      ./build/${LH_BINARY} vc \
+      ./build/"${LH_BINARY}" vc \
         --debug-level "debug" \
         --logfile-max-number 0 \
         --log-format "JSON" \
@@ -1171,7 +1168,7 @@ for NUM_NODE in $(seq 1 "${NUM_NODES}"); do
     else
       ./build/nimbus_validator_client \
         --log-level="${LOG_LEVEL}" \
-        ${STOP_AT_EPOCH_FLAG} \
+        "${STOP_AT_EPOCH_FLAG}" \
         --data-dir="${VALIDATOR_DATA_DIR}" \
         --metrics \
         --metrics-port=$(( BASE_VC_METRICS_PORT + NUM_NODE - 1 )) \
@@ -1257,7 +1254,7 @@ if [ "$LC_NODES" -ge "1" ]; then
       --trusted-block-root="${LC_TRUSTED_BLOCK_ROOT}" \
       --jwt-secret="${JWT_FILE}" \
       "${WEB3_ARG[@]}" \
-      ${STOP_AT_EPOCH_FLAG} \
+      "${STOP_AT_EPOCH_FLAG}" \
       &> "${DATA_DIR}/logs/nimbus_light_client.${NUM_LC}.jsonl" &
     PID=$!
     PIDS_TO_WAIT="${PIDS_TO_WAIT},${PID}"
diff --git a/scripts/repo_paths.sh b/scripts/repo_paths.sh
deleted file mode 100644
index ccd817de7a..0000000000
--- a/scripts/repo_paths.sh
+++ /dev/null
@@ -1,24 +0,0 @@
-if [ -z "${REPO_PATHS_SOURCED:-}" ]; then
-REPO_PATHS_SOURCED=1
-
-SCRIPTS_DIR=$( cd -- "$( dirname -- "${BASH_SOURCE[0]}" )" &> /dev/null && pwd)
-BUILD_DIR=$(cd "$SCRIPTS_DIR/../build" &> /dev/null && pwd)
-
-data_dir_for_network() {
-  NETWORK_ID=$(cat "$NETWORK/genesis.json" | jq '.config.chainId')
-  echo "$BUILD_DIR/data/$NETWORK_ID"
-}
-
-create_data_dir_for_network() {
-  NETWORK_DIR=$(data_dir_for_network)
-  mkdir -p "$NETWORK_DIR"
-  echo "$NETWORK_DIR"
-}
-
-create_jwt_token() {
-  if [ ! -f "$1" ]; then
-    openssl rand -hex 32 | tr -d "\n" >  "$1"
-  fi
-}
-
-fi
diff --git a/tests/test_blockchain_dag.nim b/tests/test_blockchain_dag.nim
index 70e6baadc1..146fd20e24 100644
--- a/tests/test_blockchain_dag.nim
+++ b/tests/test_blockchain_dag.nim
@@ -1,5 +1,5 @@
 # beacon_chain
-# Copyright (c) 2018-2024 Status Research & Development GmbH
+# Copyright (c) 2018-2025 Status Research & Development GmbH
 # Licensed and distributed under either of
 #   * MIT license (license terms in the root directory or at https://opensource.org/licenses/MIT).
 #   * Apache v2 license (license terms in the root directory or at https://www.apache.org/licenses/LICENSE-2.0).
@@ -147,41 +147,17 @@ suite "Block pool processing" & preset():
     var blocks: array[3, BlockId]
 
     check:
-      dag.getBlockRange(Slot(0), 1, blocks.toOpenArray(0, 0)) == 0
+      dag.getBlockRange(Slot(0), blocks.toOpenArray(0, 0)) == 0
       blocks[0..<1] == [dag.tail]
 
-      dag.getBlockRange(Slot(0), 1, blocks.toOpenArray(0, 1)) == 0
+      dag.getBlockRange(Slot(0), blocks.toOpenArray(0, 1)) == 0
       blocks[0..<2] == [dag.tail, b1Add[].bid]
 
-      dag.getBlockRange(Slot(0), 2, blocks.toOpenArray(0, 1)) == 0
-      blocks[0..<2] == [dag.tail, b2Add[].bid]
-
-      dag.getBlockRange(Slot(0), 3, blocks.toOpenArray(0, 1)) == 1
-      blocks[1..<2] == [dag.tail] # block 3 is missing!
-
-      dag.getBlockRange(Slot(2), 2, blocks.toOpenArray(0, 1)) == 0
-      blocks[0..<2] == [b2Add[].bid, b4Add[].bid] # block 3 is missing!
-
-      # large skip step
-      dag.getBlockRange(Slot(0), uint64.high, blocks.toOpenArray(0, 2)) == 2
-      blocks[2..2] == [dag.tail]
-
-      # large skip step
-      dag.getBlockRange(Slot(2), uint64.high, blocks.toOpenArray(0, 1)) == 1
-      blocks[1..1] == [b2Add[].bid]
-
-      # empty length
-      dag.getBlockRange(Slot(2), 2, blocks.toOpenArray(0, -1)) == 0
-
       # No blocks in sight
-      dag.getBlockRange(Slot(5), 1, blocks.toOpenArray(0, 1)) == 2
+      dag.getBlockRange(Slot(5), blocks.toOpenArray(0, 1)) == 2
 
       # No blocks in sight
-      dag.getBlockRange(Slot(uint64.high), 1, blocks.toOpenArray(0, 1)) == 2
-
-      # No blocks in sight either due to gaps
-      dag.getBlockRange(Slot(3), 2, blocks.toOpenArray(0, 1)) == 2
-      blocks[2..<2].len == 0
+      dag.getBlockRange(Slot(uint64.high), blocks.toOpenArray(0, 1)) == 2
 
     # A fork forces the clearance state to a point where it cannot be advanced
     let